Behaviour of button-groups within a <form> defined
[left-tabs]: JSON used to build tabs can now also specify the filters ...

.. to append to data-url set on ul > li > a
/qzb/echo now also returns the filters to apply to every ajax call

that results from clicking generated left-tabs
[question_on]: Not sorting by marks and topics

In the new flow, we query topic by topic anyways
Reset / re-initialize #tab-qzb-topics btn-group on shown
[quiz-builder]: Filters for liked, suggested and previously used questions added

Click on these to include / exclude questions